Philadelphia was founded in 1682. To the best of my knowledge there has never been a single natural disaster in this city since then. No cyclones, no tidal waves, no hurricanes, no earthquakes, et cetera. There has been flooding due to tropical storms, but nothing on the scale of what I would call a natural disaster.

In other countries (Korea and Egypt come to mind) one regularly hears stories about unsavory builders building buildings too tall for their foundations / structures, which then collapse and pin people inside of them. When was the last time that happened in Philadelphia?

In the USA, when a house is built in a hurricane zone, it needs to be built to withstand hurricanes. When a house is built in an earthquake zone, it needs to be built to withstand earthquakes. What happened in China? Did an earthquake occur in an area where earthquakes have never occurred?